4x - 3y + 20 = 0....4x - 3y = -21
4x - 3y = -21.....multiply by -2
5x - 6y = -25
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-8x + 6y = 42 (result of multiplying by -2)
5x - 6y = -25
---------------add
-3x = 17
x = -17/3
this system of equations has 1 solution
        
             
        
        
        
To build the table you just have to give values to t and then calculate the corresponding c a per the model.
If the model is c = 5.5 t this is the table
t          c
           5.5 t
0         5.5(0) = 0
1         5.5(1) = 5.5
2          5.5(2) = 11.0
3         5.5(3) = 16.5 
4          5.5(4) = 22.0
5          5.5(5) = 27.5
The viables solutions are all where t is equal or greater than 0. You can even use decimal values for t. You cannot use negative values for t.
        
                    
             
        
        
        
Answer:
do 49 x 49 which equals 2,401 then check it
put 2,401 square root which equals 49 
 
        
                    
             
        
        
        
Answer:
19/25 * 100 = 76%
Step-by-step explanation: